He worked in Scotland from 1981 to 1991, for the then U.S.-based Monsanto Company, and then was appointed global strategy director in the agriculture division, based in St. Louis, Missouri. In 1995 he became managing director for the company's Asia-Pacific region, and in 1998, co-president of the agriculture division.[1]

In March 2009, Grant was named one of the world's 30 most respected CEOs on Barron's annual list.[2] He was named 2010 CEO of the Year by Chief Executive magazine.[3] In 2009, Grant earned a total compensation of $10,803,757, which included a base salary of $1,391,356, a cash bonus of $1,070,382, stocks granted of $1,875,766, options granted of $5,902,039, and other compensation of $564,214.[4]